The present invention refers to a thymus derivative, thymolyphotropin (TLT), able to stimulate the differentiation and function of T lymphocytes, characterized by the fact of being active also after oral administration.
The present invention refers also to a procedure for the isolation and purification of this derivative from mammal thymus.
It is known that some peptide derivatives active on T-lymphocytes, such as thymopoietin (U.S. Pat. No. 4,077,949), THF (Thymic Humoral Factor--U.S. Pat. No. 4,250,084) and thymosin (Zatz M. M. et al., Biol. Resp. Cancer 1: 219, 1982; Low T. L. K. and Goldstein A. L., Thymus 6: 27, 1984), have been obtained from thymus gland.
It is also known that all these derivatives have the disadvantage of being therapeutically efficacious only by parenteral route.
Therefore it would be very important to have a thymus derivative active also after oral administration, in order to overcome the many inconveniences related to the parenteral administration.
This requirement is fully satisfied by thymolymphotropin described in this invention; in fact this thymic derivative presents the characteristic (very important from the point of view of therapeutical use) of being active also after oral administration.